Television lamp



March 1, 1932., SANDELL 1,847,308

TELEVIS ION LAMP Filed June 12, 1930 Patented Mar. 1, 1932 UNITED STATES PATENT OFFICE HENRY K. SAN DELL, OF CHICAGO, ILLINOIS, ASSIGNOR TO MILLS NOVELTY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS TELEVISION LAMP Application filed June 12,

This invention relates to the art of television, and particularly to an improved form of lamp for transforming the television signals into corresponding light signals.

An important object of the invention is to provide a television lamp having electrode plates which are shaped to concentrate the light generated in the lamp so as to give a more intense beam for projection 011 a screen or other image receiving area.

Further objects and advantages of the invention will be apparent as I proceed with my specification, which taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

In the drawings:

Fig. 1 is a side elevational view of the lamp;

Fig. 2 is a front elevational view of the lamp; and

Fig. 3 is a broken detail view of the electrode plates of the lamp.

Referring to the drawings in which I have shown the preferred form in which I have thus far contemplated applying the principles of my invention, the numeral 5 designates a lamp bulb which may be of the usual form employed for ordinary vacuum tubes, and the numeral 6 designates a base for supporting the bulb 5. A pair of terminal posts 7 and 8 are sealed in the base and project therefrom sufliciently to permit connection with the source of signal current supply. The bulb 5 is gas-filled, a preferred composition of the gaseous medium for this purpose being about five p0 cent. helium and ninetyfive per cent. neon. It will be understood that the lamp is connected in the usual manner in the plate circuit of the last amplifying tube of a multiple stage amplifier, much as in the manner of connection of a loud speaker in the ordinary radio amplifying circuit.

According to the invention, the television lamp is provided with a positive electrode 9 and a negative electrode 10 positioned adjacent and parallel to electrode 9. Each of these electrodes comprises a rectangular metal plate, the opposite halves of which are bent to form an angle of about 90 degrees. 50 The positive electrode 9 is connected with 1930. Serial No. 460,848.

the post 7 by a pair of wires 11, and the negative electrode 11 is connected with the post 8 by a pair of wires 12. The wires 12 may be sealed in a glass housing 13 to prevent danger of shorting with the wires 11. The bending of the electrode plates 9 and 10 in the manner shown tends to greatly concentrate the light generated in the lamp. In lamps of this type the light is generated for the most part on the side or area of the negative plate 10 which is most remote from the positive late 12. The inner face of the plate 10, t erefore, may be considered as the active area from the standpoint of generation of light. The plate is positioned with its angular opening facing the point of image reception,

which in the accompanying drawings is assumed to be to the right, viewing Fig. 1, and

the plate 9 is positioned in back of and parallel to the plate 10.

By positioning the opposite halves of the plate 10 at an angle to the line of light projection a greater depth of the glowing gas adjacent the inner surface of plate 10 is utilized to give a more intense illumination for a given plate area than would be obtained with the plate in a position at right an les to the line of vision or light projection. B urthermore by making the opposite halves of the plate intersect in this manner a portion of the light generated on the lower half of plate 10 will be reflected from the upper half of the plate toward the point of image reception, and similarly light generated on the upper half of plate 10 will be reflected from the lower half of the platetoward the point of image reception. This reflection of light tends to augment the concentration obtained by positioning the active areas of the plate at an angle to the line of vision. In actual practice it has been found that by using this form of electrode, together with a suitable condensing lens, a beam of light may be obtained which is about five times as strong as that obtainable from a lamp having the ordinary flat electrode plate.

The invention permits the use of much smaller electrode plates in the lamp, inasmuch as for a given generating plate area a much stronger light beam is obtained than 2 names in the case of the flat late electrode. This is an important factor m the standpoint of inductance. The use of small plates decreases the inductance of the lamp, and hence 5 fewer amplifyin tubes need be used to o erate the lamp. is, in turn, tends to m e for a sharper'picture, since each additional tube in the amplifying system adds inductance to the circuit which tends to decrease the sharpness ofthe reproduced image.

While I have shown the electrode plates as bent to approximate a right angle, it will be apparent that more or less concentration of light can be obtained by using curved plates.

For example, plates formed to approximate a parabola opening toward the point of ima e reception would tend to concentrate the lig t emanating from theinner surfaces of the plate 10. Such modifications are to be viewed as fully within the sco of the mvention. Also, it is to be un erstood that the shape of the plates need not necessarily be rectangular since this is considered merely a preferred form.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations shoul be understood therefrom, but the appended claims should be construed as broadly as permissible in View of the prior art.

What I regard as new and desire to secure by Letters Patent is:

1. A television lamp comprising a sealed envelope having posit1ve and negative electrodes positioned therein, said negative electrode being in the form of a late bent to form an angle of approximate y ninety degrees, said angle opemng away from the positive electrode.

2. A television lamp comprising a sealed envelope having posit1ve and negative electrodes positioned therein, said negative electrode being in the form of a late bent to form an angle of approximate y ninety degrees, said angle opening away from the positive electrode, and a positive electrode comprising a plate bentto a similar angle and ying in parallel spaced relation to the negative electrode plate. In witness whereof, I hereunto subscribe my name to this specification.

HENRY K. SANDELL. 

